The study of Automated Diagnosis in Radiology is part of an overall effort to understand the perceptual process in Radiology. We undertook a study and review of approaches to automated radiologic diagnosis. As an outgrowth of this, we approach the problem of the decision process in deep venous thrombosis as one which was amenable to decision analysis. A critical appraisal of receiver-operating characteristics. It became important for us to approach the question of the context in which ROC analyses are worthwhile and the distinction between the use of such techniques in a purely theoretical framework and that which can be applied in the clinical setting. A paper entitled ROC Analysis in Content focused attention on the utility and limitations of ROC analyses in clinical settings. During this period, we have further refined a two stage detection model developed with Dr. Swensson in our laboratory. This model treats the detection of targets in a visual search task as a concatenation of two serial detection stages. Resident film interpretations and staff review: Benefits and Costs. This study was undertaken to assess the perceptual process by which residents interpret films on their own and then have them reviewed by staff radiologists. The importance of this study is heightened by our finding that 22 percent of plain film examinations in our department were interpreted outside of normal hours by residents working alone with staff consultation available at all times. These studies were reviewed the following morning by staff radiologists. The reviewing process, a major method of radiology resident education, was designed to assure accurate film interpretation. The benefits and costs of this system was analyzed in order to assess, in a real-life setting, the perceptual process in radiology as practiced by those in training.